A television centering circuit is employed for centering the electron beam raster produced on the kinescope screen with respect to an opening in the TV cabinet. For example, the raster may have to be moved either to the right or to the left to center it relative to the cabinet opening. Conventional centering circuits of this type require some means for selectively connecting an input terminal to one of a pair of output terminals or to neither of them.
One way of achieving the above interconnections is shown in FIG. 1. A jumper connector 10 is used in conjunction with a set of 3 connector stakes A, B and C fixedly disposed on a printed circuit board (PCB) 12. In the position shown in the solid lines, the jumper connector 10 connects the connector stake A with the connector stake B. When the jumper connector 10 is moved to a position depicted by the phantom lines, the connector stake A is connected with the connector stake C. The above jumper connector arrangement is unsuitable for automatic centering operation because of the complicated motions required for moving the connector 10 between the two positions. Another drawback of this arrangement is that if a no-connection position is desired, an extra connector stake is needed. A further deficiency of the jumper connector arrangement is relatively high cost of parts and labor.
Alternately, the interconnections between an input terminal and a pair of output terminals can be accomplished by using a slide switch. The slide switch generally suffers from the same drawbacks--namely, not amenable to automation, lack of a no-connection position and relatively high cost of parts and labor.